Dielectric and Spontaneous Polarization Studies of a Ferroelectric Chiral Smectic Liquid Crystal

• 作者: Abraham K. George C. Carboni D. M. Potukuchi S. H. Al-Harthi W. M. Zoghaib
• 来源期刊: 凝固态物理国际期刊(英文)
• 学科: 化学
• 关键词: SMECTIC C* and SMECTIC A*de Vries PHASES DIELECTRIC PERMITTIVITY DIELECTRIC Relaxation Activation Energy SPONTANEOUS Polarization
• 年，卷（期）: ngtwlgjqkyw,（2）
• 页码范围: 75-79
• 页数: 5页
• 分类号: O6

摘要

Dielectric relaxation and spontaneous polarization studies have been carried out in a low molar mass organosiloxane liquid crystal, TSi10PPBN4 which displays a wide temperature range of de Vries Smectic A* and chiral Smectic C* phases. The temperature variation of the permittivity and dielectric loss studied are found to have anomalous variations in the vicinity of the phase transitions. The frequency variation of permittivity and dielectric loss are also studied in the de Vries Smectic A* and Smectic C* phases. The relaxation frequency, fR is found to decrease with decreasing temperature. Temperature variation of fR is found to follow an Arrhenius shift from which the activation energy is estimated. The thermal variation of the spontaneous polarization, Ps is measured using the polarization reversal technique in the Smectic C* phase. Ps increases initially, reaches a peak value and then drops drastically in the vicinity of the SmC*-SmA*de Vries phase transition.